Home › Salads › Potato Mayonnaise
Potato Mayonnaise
Very small baked potato 1 teaspoon mustard 1 teaspoon salt 1 teaspoon powdered sugar 2 tablespoons vinegar ¾ cup olive oil Remove and mash the inside of potato. Add mustard, salt, and powdered sugar; add one tablespoon vinegar, and rub mixture through a fine sieve. Add slowly oil and remaining vinegar. By the taste one would hardly realize eggs were not used in the making.
An eggless mayonnaise that leans on potato starch and mashed potato solids to hold the oil in suspension. It works, but the proportions want checking as you go.
- The hinge: the potato must be dry and hot-bakedThe hinge: the potato is baked, not boiled -- Baking drives off water and leaves drier, mealier flesh, which is probably why it is specified here; a wetter boiled or steamed potato is more likely to give a slack, loose dressing. The recipe itself gives no reason.
- "Very small" baked potatoGenuinely ambiguous. Roughly 3 oz raw, giving something like 1/4 cup of mashed flesh, is a sensible starting point; err on the small side, since too much potato simply gives you seasoned mashed potato.
- Mustard means dry mustardMustard almost certainly means dry mustard -- Unqualified "mustard" in a dressing of this period generally indicates the powder rather than prepared jarred mustard. Mustard powder is also thought to help an emulsion along, as well as adding heat.
- Powdered sugarIn this period the term meant sugar ground fine, not modern confectioners' sugar with its cornstarch. Either will do here; if using granulated, dissolve it in the vinegar first.
- The salt is highA teaspoon of salt in what amounts to half a cup of dressing is aggressive by current palates. Start with a third of it and adjust at the end.
- Sieve, or a blenderThe fine sieve exists to break up potato lumps before the oil goes in; a small food processor or immersion blender does the same work in seconds. Note that a blender turns some extra-virgin olive oils harshly bitter, so a mild oil is safer.
- Add the oil slowly, then loosenDrizzle the oil in as you would for egg mayonnaise. The remaining vinegar goes in last, partly for flavor and partly to thin a mixture that will have stiffened.
- Yield and keepingSomething over half a cup, enough to dress a salad for three or four. It contains cooked potato, so refrigerate and use within a day or two; it will thicken when cold and needs stirring.
Eggless dressings like this are often said to have served households counting the cost of eggs as well as cooks feeding invalids or people who could not tolerate them, though how widely each motive applied is uncertain. Fannie Farmer's book, first published in 1896 out of the Boston Cooking School, is unusually systematic about offering variants on a base preparation, and its salad chapter runs through mayonnaise in several forms alongside boiled and French dressings. The technique here appears to be sound food science arrived at by kitchen observation: gelatinized potato starch and the mucilage in mustard powder are generally thought to stabilize an oil-in-water emulsion somewhat as egg yolk lecithin does. The closing line, that no one would guess eggs were absent, reads as a familiar way of recommending a substitution in the economical cookery of the era.